AP Computer Science Exam Question

Question:

Consider the following Java code snippet:

public class ExceptionHandlingExample {

    public static void main(String[] args) {
        String[] names = {"Alice", "Bob", "Charlie", "David"};

        try {
            for (int i = 0; i <= names.length; i++) {
                System.out.println(names[i]);
            }
        } catch (ArrayIndexOutOfBoundsException e) {
            System.out.println("An exception occurred: " + e.getMessage());
        } finally {
            System.out.println("Program execution completed.");
        }
    }
}

If the above code is executed, what will be the output?

A) Alice B) Bob C) Charlie D) David E) An exception occurred: Array index out of range F) An exception occurred: Array index out of bounds G) An exception occurred: null H) Program execution completed. I) None of the above.

Answer:

The correct answer is E) An exception occurred: Array index out of range.

Here's a step-by-step explanation of the code execution:

1. The code declares a String array names with four elements: "Alice", "Bob", "Charlie", and "David".
2. The code enters a try block where it tries to access elements from the names array using a for loop.
3. The loop runs from i = 0 to i <= names.length, which means it will iterate 5 times (0, 1, 2, 3, 4).
4. Inside the loop, the code attempts to print names[i], starting from i = 0. This will successfully print "Alice", "Bob", "Charlie", and "David" in separate lines.
5. However, when i becomes 4, which is beyond the index range of the names array, an ArrayIndexOutOfBoundsException is thrown.
6. The catch block catches the exception and executes the corresponding code block, which prints "An exception occurred: Array index out of range".
7. Finally, the code block inside the finally block is executed, which prints "Program execution completed.".

Therefore, the final output will be:

Alice
Bob
Charlie
David
An exception occurred: Array index out of range
Program execution completed.